Typical printed circuit board inspection devices perform only DC open/short inspections of the status of board wiring without determining whether degree of coupling meets specifications. Moreover, these devices have been unable to determine whether responses of a digital semiconductor element having a hysteresis input circuit against RZ signals meet a defined rage.
Thus, to inspect a printed circuit board constituting a bus using a directional coupler and a semiconductor element, printed circuit board inspection devices are known which use TDR (Time Domain Reflectometry) methods to inspect whether the degree of coupling is within specified values and to inspect whether responses to voltage and pulse-width times of polar RZ signals are within specified values (for example, refer to PLT 1). TDR methods are common as impedance measurement methods such as for transmission lines as well as printed circuit boards and are suitable for measuring impedance characteristics such as in cables including interface cables used to transmit data signals such as clock pulses.
However, the printed circuit board inspection device described in PLT 1 is not a multifunctional substrate inspection apparatus capable of performing multiple types of inspections on both sides of a substrate in multiple stages by selectively bringing only respectively required probes into contact with one of the both sides of a substrate.
Furthermore, circuit board inspection jigs with high degrees of freedom for positioning and insertion direction of a camera for fine adjustment of relative positioning of a circuit board under inspection and the jig while saving space for storing the jig are also known (for example, see PLT 2).
This circuit board inspection jig has a custom jig portion corresponding to specifications of the circuit board under inspection and a common jig portion which is commonly used; the custom jig portion includes a probe holding board holding probes in positions corresponding to each test point of the circuit board under inspection and which brings each of the probes into contact with each of the test points, conductors in contact with one end of each probe of the probe holding board, and a test point collecting board connected with the other end of the conductors, and the common jig portion has a probe block holding probes in contact with the other end of each of the conductors of the test point collecting board and a connector connection board in contact with probes of the probe block to determine the conduction status of each inspection contact on the circuit board to be inspected via the connector connection board.
However, the circuit board inspection jig described in PLT 2 is not a multifunctional substrate inspection apparatus capable of performing multiple types of inspections on both sides of a substrate in multiple stages by selectively bringing only respectively required probes into contact with one of the both sides of a substrate.